didn't get it. The horrific highway crash that seriously injured TV star Tracy Morgan the driver of the tractor-trailer that triggered the crash has been charged. This morning, the limo driver is recou recounting what happened. ABC's gio Benitez. Reporter: Good morning, to you, bianna, Morgan right now in the intensive care unit at the hospital. His family by his side. This morning, we're learning a whole lot more about that horrific crash It felt like an explosion. Reporter: This morning, the limo driver is speaking out as we get a new look at the aftermath of that dramatic car crash. Leaving three in critical condition and killing one. I climbed around and heard Tracy screaming for help. Reporter: This instagram posted just before the crash, showing Morgan and his team were all smiles after a stand-up routine in Delaware, on their way back to New York City. A great show in Dover. Tracy was holding his baby before we left. Reporter: Police sources tell ABC news, that the truck driver was driving this Walmart tractor-trailer early Saturday morning and failed to see the slow traffic ahead. I don't know if we flipped several times or one time. Reporter: The truck swerved to avoid the limo bus, but the truck slammed into it. He's been charged with one count of death by auto and four counts of assault by auto, roper was arrested late Saturday. Morgan we're told has head injuries. Now his friends and colleagues are sending messages of support. I don't know who I am anymore, he's perhaps best known for his TV role on 30 rock and his decade on Saturday night live. Remember, sources say that the truck driver was driving that Walmart truck you saw in the video, Walmart telling ABC news, we're profoundly sorry that one of our trucks were involved. Dan? Gio, thank you. We're pulling for Tracy Morgan.

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